A Multi-Protocol Label Switched (MPLS) network is a communication network made up of a plurality of network devices which transfer or forward packets of information using so-called virtual connections referred to as “label switched paths” (LSPs). Each MPLS network device may be a router, switch, or other device that is capable of processing packets in accordance with MPLS standards and the like.
A conventional LSP begins at a source network device, passes through intermediate network devices and ends at a destination network device.
If a failure at a network device or link (failure point) occurs downstream of a source network device, so-called MPLS “Fast Re-routing” is employed to bypass the failure point.
Existing MPLS Fast Re-route techniques rely on the use of MPLS forwarding tables to re-route traffic traversing a primary path to an alternate path provided a failure point does not occur at an ingress region of the primary path (i.e., along an outgoing link associated with a source network device or at a network device which neighbors the source network device, a so-called neighboring device), where such tables are of little use. Still further, there is no guarantee that the resultant alternate LSPs will have the same quality of service as an original, primary LSP.